I will try to reply to some of your questions to the extent I have anything that might be useful. I have just been involved in a year long renovation of Willow Oaks Country Club, a golf course in Richmond, VA, on the banks of the James River. I was involved as a Club member so take my observations with a grain of salt.
Our renovation was done by Lester George, who posts regularly on this board. Lester did a phenomenal design job on a difficult property to work with due to its lack of elevation changes. It was basically a pool table before we started the project. I would highly recommend that you contact Lester for more information. He has also been involved in design issues on other river front courses.
The site of the course - particularly the fact that the lower half of the course is in the flood plain of the river - definitely posed some unique problems. There is a description of the project, including numerous explanatory videos we made during the project, available here:
Willow Oaks RenovationHere is an aerial photo of the property mid-renovation:
Here is a stab at answers to SOME of your questions (your questions in bold) based on what I know:
"What are the perks and pitfalls of golf course construction along or near a river?"Perks: Probably going to provide some great scenery for great hole possibilities.
Pitfalls: (1) Likely to have flooding problems. (2) Drainage problems if area near river is flat (likely).
"Are there any similarities between linksland and land bordering a river?"Not in our case. It probably depends on the type of silt that has accumulated on the site during flood events over the years.
"Are there any unique maintenance challenges during the development and maturity of the course?"Not really as far as I am aware. In our case, we are in the transition zone and so that in itself poses big headaches for the superintendent. In the property nearest the river, it is exceptionally hot and humid during the summer causing problems. The heat and humidity just sit there with very little air movement.
"Is it easier to grow and maintain turf on these sites than other locations?"I don't think it is any more or less problematic. If you are in an area where the river will overtake the course during floods, you will need to be careful with grass selections. Delicate delicate grasses may not like being under water for days! Lester George has been quite bold in his use of bentgrass in this area of the country but nonetheless advised us against bentgrass for this reason, as well as others.
"Does the site require more or less earthmoving than an inland or linksland site?"I suspect it is highly likely you will need more earthmoving in order to get necessary elevation changes on course for drainage. We moved around 130,000 cubic yards in order to dig a couple borrow ponds.
"Is it easier or more difficult to work the land than an inland or linksland site?"Probably no more or less difficult.
"Is it more difficult to create interesting/quirky/sporty holes on a riverside location?"I would think it should be no more nor less difficult. I do suspect you should be able to get a dramatic hole or two on the river, depending on your site though.
I hope this is somewhat helpful.
Good luck!